Device for controlling the upper threads of sewing-machines.



D. W. COREY. DEVICE FOR CONTROLLING THE UPPER THREADS 0F SEWINGMAOHINES.

APPLIOATIONPILBD MAY 21, 1901.

Patented 0011. 15, 1912.

UNITED STATES PATENT anion- DANIEL w. COREY, or cnroAeo, ILLINoIs, ASSIGNOR T0 UNIoN SPECIAL SEWING MACHINE 00., or CHICAGO, ILLINo-Is, A CORPORATION or ILLINOIS.

nEvIcn FOR. CONTROLLING THE UPPER 'rIInnAns or'sn'wINe-MAcHINEs.

Specification of LettersPatent. Application filed May 21, 1901. Serial No. 6 1,291.

Patented Oct. 15,1912.

To all whom it may concern:

' Be it known that I, DANIEL W. COREY, a citizen ofthe United States, residing at Chicag'o, in the countyof Cook, State of Illinois, have invented certain new, and useful Improvements in Devices for Controlling the Upper Threads of Sewing-Machines, of which the following is a description, reference being had to the accompanying drawing and to the letters and figures ofrefer- .ence marked thereon.

My invention relates to an lmprovement in sewingmachines, and particularly toa device for controlling the upper threads.

. The object of the invention is to provide an attachment for sewing machines for sewing leather, which will in the downward movement of the needles grasp the thread at the proper time and prevent the needles carrying down too much thread, which will leave too Inuch of the needle threads showingon the under side of the seam; thus givan unsightly appearance to the under of the seam, and also preventing the proper drawing of the threadinto the goods.

The invention has been designed particuany for use in connection with chain-stitch sewing machines, of the Union Special type, adapted'for vamping shoes, such as illus trated in Patent 547,675, granted October 8, 1895, to Lansing Onderdonk.

The invention conslsts in the matters hereinafter described and referred to in the appended claims.

The inventionis illustrated in the accompanying drawings, in whichi Figure 1 is a side elevation of'a Union Special left hand cylinder vamping machine, showing my invention applied thereto; Fig. 2 is a perspective view showing the detail views respectively, of the clamping jaws and member operating thereon.

In these drawings, A represents the cylindrical bed plate or casing of a Union Special cylinder vamping machine, B is the goose-neck, C the needle lever, D the needles.

The needle lever O is pivoted to the overhanging arm as usual and receives its osc1llation from a link G, operated from an eccentricC carried by the main shaft C The upper thread or threads a are led from the tension or tensions T throughthe eyelet-b on the needle lever, the eyelet a on the gooseneck, the eyelet cl on the needle lever, the eyelet e on the head of the machine, and the eyelet on the top of the needle bar. -As the needle bar moves np,'t'he thread is-drawn taut against the stationary eyelet e, and pulls ofi from the spools. As the needle bar descends, there-is danger of the needle carrying too much thread into the goods, and to avoid this, I have devised the mechanism forming the subject matter of this in-, vention. I

Attached to the goose-neck or stationary part of the machine frame, by a set screw 9 is-a metallic plate h, to the upper end of which are secured two spring plates i, k,

held from lateral displacement by stop pins Z, and ndrmally separated at their lower endsto allow the thread a to slip between them. The upper spring plate 2' is formed adjacent its lower end with a raised portion m. I

Upon the needle lever C issecured a metallic plate u, having at its upper end a lug or projection 0, adjustably secured set screw 7), said plate at being attached to the shown in the drawings. As it passes up it necessarily draws the thread around this thread eyelet and thus pulls it through the The thread,

tensions or from the spools. after being drawn oil, is of course given up as the needle'bargoes down. and in. the operation of the needle lever, the thread eyelet d moving through the arc of the circle with the needle lever takes up partly the thread or straightens it out.

' The clamping device can be clamped at any time during the downward motion of theneedle bar, but it is released from the thread in time for the feed dog to move the fabric forward and thus not try to move the fabric with the resist of the clamping device upon the thread. The clamping defrom-t X Having thus described my invention, what.

vice prevents the feeding of fresh thread from the spools and through the tensions when the needles begin to start on their upward stroke. The friction of the material against the threads while in the material and carried by the needle, is sufficient, in heavy work like crossing seams in vamping shoes, to-- overcome the friction exerted on the thread by the tension device, thus caus-l in an extra amount of thread tobe drawn 0 from the spools when the nipper spring is not used, which leaves loose loops of needle thread on the under surface of the fabric. In other words, the friction of the material against the thread when the needles are in the goods is greater than the tension upon the thread, consequently itwould pull from the weak point. The nipper was put on to avoid this pulling of fresh thread. The clamping of the thread takes place at just about the time the eye of the needle passes through the material and released again just before the feed dog engages the fabric to move it forward. a

Various modifications in the construction of the parts, may be made without departing e spirit of my invention.

I claim as new, and desire to secure by Letters Patent, is: v

1. A sewing machine comprising stitch foi'mi-ngmechanism, including a reciprocatiug needle, means for drawing thread from the supply, a tension device, clamping jaws for the needle thread located between the supply and the means for drawing off the thread, and a member movable with the needle and cooperating with the clamping jaws to cause said jaws to alternately clamp and release the thread, and means for imparting movement to the movable member, whereby the jaws of the clamp will be closed during substantially the entire time the needle eye is beneath the material.

ing jaws attached-to a stationary art of the machine frame, said jaws being ocated be-' tween the su ply and the means for drawin thread from the supply, a member attache to said needle lever 'and engaging said jaws, to cause them to alternately clamp and release the thread, and means for operating the movable member to close the thread clamping jaws on the needle thread during substantially the entire time the needle eye is beneath the material.

3. In a sewing machine having a reciprocating needle, a needle lever, a plate secured to thegoose-neck of the machine, a spring plate secured thereto and 'movable to grasp the needle thread, a plate attached sprin plate; substantially as described.

4. n asewing machine having a reciprocating needle, a needle lever, a plate secured to the goose neck of the machine, a spring plate secured thereto, a plate attached to the needle lever, having on its upper end an angular projection, and a slotted plate adjustably secured thereto and adapted. to engage and release the spring plate; substantially as described.

In testimony whereof I afiix my signature,

in presence of two witnesses.

DANIEL W. COREY. Witnesses:

M. O. MOORE, GUY G. SEAMAN.

Copies of this patent may be obtained for five cents each, by addressing the Washington, I). 0.

65 to the needle lever, having an adjustable pro-. jection adapted to engage and release the. 

